From patchwork Tue Jul 2 17:10:58 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hartley Sweeten X-Patchwork-Id: 256467 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:770:15f::2]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 99CFC2C009F for ; Wed, 3 Jul 2013 03:12:41 +1000 (EST) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Uu47l-0006SA-BH; Tue, 02 Jul 2013 17:12:17 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Uu47j-0004ES-F6; Tue, 02 Jul 2013 17:12:15 +0000 Received: from mail1.bemta8.messagelabs.com ([216.82.243.206]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Uu47f-0004Dd-U1 for linux-mtd@lists.infradead.org; Tue, 02 Jul 2013 17:12:13 +0000 Received: from [216.82.242.99:5857] by server-14.bemta-8.messagelabs.com id 47/D1-02859-3D903D15; Tue, 02 Jul 2013 17:11:47 +0000 X-Env-Sender: hartleys@visionengravers.com X-Msg-Ref: server-16.tower-131.messagelabs.com!1372785103!22637178!8 X-Originating-IP: [216.166.12.69] X-StarScan-Received: X-StarScan-Version: 6.9.9; banners=-,-,- X-VirusChecked: Checked Received: (qmail 28348 invoked from network); 2 Jul 2013 17:11:47 -0000 Received: from out001.collaborationhost.net (HELO out001.collaborationhost.net) (216.166.12.69) by server-16.tower-131.messagelabs.com with RC4-SHA encrypted SMTP; 2 Jul 2013 17:11:47 -0000 Received: from etch.local (10.2.3.210) by smtp.collaborationhost.net (10.2.0.118) with Microsoft SMTP Server (TLS) id 8.3.213.0; Tue, 2 Jul 2013 12:11:17 -0500 From: H Hartley Sweeten To: linux-mtd Subject: [PATCH v2 10/11] spi: spi-ep93xx: convert to the queued driver infrastructure Date: Tue, 2 Jul 2013 10:10:58 -0700 User-Agent: KMail/1.9.9 MIME-Version: 1.0 Content-Disposition: inline Message-ID: <201307021010.59345.hartleys@visionengravers.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130702_131212_071938_7902AA03 X-CRM114-Status: GOOD ( 24.43 ) X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [216.82.243.206 listed in list.dnswl.org] -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines Cc: David Brownell , Ryan Mallon , mika.westerberg@iki.fi, hsweeten@visionengravers.com, grant.likely@linaro.org, spi-devel-general@lists.sourceforge.net X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org The SPI core provides infrastructure for standard message queueing. Use that instead of handling it in the driver. Signed-off-by: H Hartley Sweeten Acked-by: Mika Westerberg Cc: Ryan Mallon Cc: Mark Brown Cc: Grant Likely --- drivers/spi/spi-ep93xx.c | 165 ++++++----------------------------------------- 1 file changed, 19 insertions(+), 146 deletions(-) diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c index 2e64806..4c9a50c 100644 --- a/drivers/spi/spi-ep93xx.c +++ b/drivers/spi/spi-ep93xx.c @@ -26,7 +26,6 @@ #include #include #include -#include #include #include #include @@ -70,19 +69,13 @@ /** * struct ep93xx_spi - EP93xx SPI controller structure - * @lock: spinlock that protects concurrent accesses to fields @running, - * @current_msg and @msg_queue * @pdev: pointer to platform device * @clk: clock for the controller * @regs_base: pointer to ioremap()'d registers * @sspdr_phys: physical address of the SSPDR register * @min_rate: minimum clock rate (in Hz) supported by the controller * @max_rate: maximum clock rate (in Hz) supported by the controller - * @running: is the queue running - * @wq: workqueue used by the driver - * @msg_work: work that is queued for the driver * @wait: wait here until given transfer is completed - * @msg_queue: queue for the messages * @current_msg: message that is currently processed (or %NULL if none) * @tx: current byte in transfer to transmit * @rx: current byte in transfer to receive @@ -96,30 +89,15 @@ * @tx_sgt: sg table for TX transfers * @zeropage: dummy page used as RX buffer when only TX buffer is passed in by * the client - * - * This structure holds EP93xx SPI controller specific information. When - * @running is %true, driver accepts transfer requests from protocol drivers. - * @current_msg is used to hold pointer to the message that is currently - * processed. If @current_msg is %NULL, it means that no processing is going - * on. - * - * Most of the fields are only written once and they can be accessed without - * taking the @lock. Fields that are accessed concurrently are: @current_msg, - * @running, and @msg_queue. */ struct ep93xx_spi { - spinlock_t lock; const struct platform_device *pdev; struct clk *clk; void __iomem *regs_base; unsigned long sspdr_phys; unsigned long min_rate; unsigned long max_rate; - bool running; - struct workqueue_struct *wq; - struct work_struct msg_work; struct completion wait; - struct list_head msg_queue; struct spi_message *current_msg; size_t tx; size_t rx; @@ -230,7 +208,7 @@ static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi, /* * Make sure that max value is between values supported by the * controller. Note that minimum value is already checked in - * ep93xx_spi_transfer(). + * ep93xx_spi_transfer_one_message(). */ rate = clamp(rate, espi->min_rate, espi->max_rate); @@ -306,54 +284,6 @@ static int ep93xx_spi_setup(struct spi_device *spi) } /** - * ep93xx_spi_transfer() - queue message to be transferred - * @spi: target SPI device - * @msg: message to be transferred - * - * This function is called by SPI device drivers when they are going to transfer - * a new message. It simply puts the message in the queue and schedules - * workqueue to perform the actual transfer later on. - * - * Returns %0 on success and negative error in case of failure. - */ -static int ep93xx_spi_transfer(struct spi_device *spi, struct spi_message *msg) -{ - struct ep93xx_spi *espi = spi_master_get_devdata(spi->master); - struct spi_transfer *t; - unsigned long flags; - - if (!msg || !msg->complete) - return -EINVAL; - - /* first validate each transfer */ - list_for_each_entry(t, &msg->transfers, transfer_list) { - if (t->speed_hz && t->speed_hz < espi->min_rate) - return -EINVAL; - } - - /* - * Now that we own the message, let's initialize it so that it is - * suitable for us. We use @msg->status to signal whether there was - * error in transfer and @msg->state is used to hold pointer to the - * current transfer (or %NULL if no active current transfer). - */ - msg->state = NULL; - msg->status = 0; - msg->actual_length = 0; - - spin_lock_irqsave(&espi->lock, flags); - if (!espi->running) { - spin_unlock_irqrestore(&espi->lock, flags); - return -ESHUTDOWN; - } - list_add_tail(&msg->queue, &espi->msg_queue); - queue_work(espi->wq, &espi->msg_work); - spin_unlock_irqrestore(&espi->lock, flags); - - return 0; -} - -/** * ep93xx_spi_cleanup() - cleans up master controller specific state * @spi: SPI device to cleanup * @@ -801,50 +731,29 @@ static void ep93xx_spi_process_message(struct ep93xx_spi *espi, ep93xx_spi_disable(espi); } -#define work_to_espi(work) (container_of((work), struct ep93xx_spi, msg_work)) - -/** - * ep93xx_spi_work() - EP93xx SPI workqueue worker function - * @work: work struct - * - * Workqueue worker function. This function is called when there are new - * SPI messages to be processed. Message is taken out from the queue and then - * passed to ep93xx_spi_process_message(). - * - * After message is transferred, protocol driver is notified by calling - * @msg->complete(). In case of error, @msg->status is set to negative error - * number, otherwise it contains zero (and @msg->actual_length is updated). - */ -static void ep93xx_spi_work(struct work_struct *work) +static int ep93xx_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) { - struct ep93xx_spi *espi = work_to_espi(work); - struct spi_message *msg; + struct ep93xx_spi *espi = spi_master_get_devdata(master); + struct spi_transfer *t; - spin_lock_irq(&espi->lock); - if (!espi->running || espi->current_msg || - list_empty(&espi->msg_queue)) { - spin_unlock_irq(&espi->lock); - return; + /* first validate each transfer */ + list_for_each_entry(t, &msg->transfers, transfer_list) { + if (t->speed_hz < espi->min_rate) + return -EINVAL; } - msg = list_first_entry(&espi->msg_queue, struct spi_message, queue); - list_del_init(&msg->queue); - espi->current_msg = msg; - spin_unlock_irq(&espi->lock); - ep93xx_spi_process_message(espi, msg); + msg->state = NULL; + msg->status = 0; + msg->actual_length = 0; - /* - * Update the current message and re-schedule ourselves if there are - * more messages in the queue. - */ - spin_lock_irq(&espi->lock); + espi->current_msg = msg; + ep93xx_spi_process_message(espi, msg); espi->current_msg = NULL; - if (espi->running && !list_empty(&espi->msg_queue)) - queue_work(espi->wq, &espi->msg_work); - spin_unlock_irq(&espi->lock); - /* notify the protocol driver that we are done with this message */ - msg->complete(msg->context); + spi_finalize_current_message(master); + + return 0; } static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id) @@ -984,7 +893,7 @@ static int ep93xx_spi_probe(struct platform_device *pdev) return -ENOMEM; master->setup = ep93xx_spi_setup; - master->transfer = ep93xx_spi_transfer; + master->transfer_one_message = ep93xx_spi_transfer_one_message; master->cleanup = ep93xx_spi_cleanup; master->bus_num = pdev->id; master->num_chipselect = info->num_chipselect; @@ -1002,7 +911,6 @@ static int ep93xx_spi_probe(struct platform_device *pdev) goto fail_release_master; } - spin_lock_init(&espi->lock); init_completion(&espi->wait); /* @@ -1031,23 +939,13 @@ static int ep93xx_spi_probe(struct platform_device *pdev) if (info->use_dma && ep93xx_spi_setup_dma(espi)) dev_warn(&pdev->dev, "DMA setup failed. Falling back to PIO\n"); - espi->wq = create_singlethread_workqueue("ep93xx_spid"); - if (!espi->wq) { - dev_err(&pdev->dev, "unable to create workqueue\n"); - error = -ENOMEM; - goto fail_free_dma; - } - INIT_WORK(&espi->msg_work, ep93xx_spi_work); - INIT_LIST_HEAD(&espi->msg_queue); - espi->running = true; - /* make sure that the hardware is disabled */ ep93xx_spi_write_u8(espi, SSPCR1, 0); error = spi_register_master(master); if (error) { dev_err(&pdev->dev, "failed to register SPI master\n"); - goto fail_free_queue; + goto fail_free_dma; } dev_info(&pdev->dev, "EP93xx SPI Controller at 0x%08lx irq %d\n", @@ -1055,8 +953,6 @@ static int ep93xx_spi_probe(struct platform_device *pdev) return 0; -fail_free_queue: - destroy_workqueue(espi->wq); fail_free_dma: ep93xx_spi_release_dma(espi); fail_release_master: @@ -1070,29 +966,6 @@ static int ep93xx_spi_remove(struct platform_device *pdev) struct spi_master *master = platform_get_drvdata(pdev); struct ep93xx_spi *espi = spi_master_get_devdata(master); - spin_lock_irq(&espi->lock); - espi->running = false; - spin_unlock_irq(&espi->lock); - - destroy_workqueue(espi->wq); - - /* - * Complete remaining messages with %-ESHUTDOWN status. - */ - spin_lock_irq(&espi->lock); - while (!list_empty(&espi->msg_queue)) { - struct spi_message *msg; - - msg = list_first_entry(&espi->msg_queue, - struct spi_message, queue); - list_del_init(&msg->queue); - msg->status = -ESHUTDOWN; - spin_unlock_irq(&espi->lock); - msg->complete(msg->context); - spin_lock_irq(&espi->lock); - } - spin_unlock_irq(&espi->lock); - ep93xx_spi_release_dma(espi); spi_unregister_master(master);